What is what kind of sponge is spongebob?

SpongeBob SquarePants is a fictional character from a popular animated television series of the same name. He is a sea sponge who lives in a pineapple under the sea in the fictional underwater city of Bikini Bottom. SpongeBob is known for his upbeat and optimistic personality, as well as his love of jellyfishing, bubble-blowing, and Krabby Patties.

In the show, SpongeBob works as a fry cook at the Krusty Krab restaurant, alongside his grumpy neighbor Squidward Tentacles and his boss, Mr. Krabs. SpongeBob's best friends are Patrick Star, a dim-witted starfish, and Sandy Cheeks, a scientist squirrel who lives in an air dome.

Although SpongeBob is a sea sponge, his appearance is more like a synthetic kitchen sponge with a square shape. This is a deliberate artistic choice by creator Stephen Hillenburg to make SpongeBob instantly recognizable and unique.